US4783265A - Water treatment - Google Patents
Water treatment Download PDFInfo
- Publication number
- US4783265A US4783265A US06/925,500 US92550086A US4783265A US 4783265 A US4783265 A US 4783265A US 92550086 A US92550086 A US 92550086A US 4783265 A US4783265 A US 4783265A
- Authority
- US
- United States
- Prior art keywords
- water
- composition
- iii
- electrolyte
- amount
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
- C02F1/5236—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using inorganic agents
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
- C02F1/54—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using organic material
Definitions
- This invention relates to water treatment, and particulalry, although not exclusively, to the treatment of waste water containing organic particles such as sewage.
- British Patent Application No. 8208603 discloses a composition for conditioning an aqueous system, the composition comprising particles of an alkaline earth metal hydroxide and an anionic oligomeric polyelectrolyte.
- This composition tends to raise the pH of the aqueous system to which it is added, particularly if the aqueous system comprises relatively soft water.
- the alkalinity of the composition may have a destabilising effect on the anionic oligomeric polyelectrolyte which means that the effectiveness of the composition tends to deteriorate with time.
- a method of treating water comprising adding to the water a composition comprising a weighting agent and an electrolyte having a multivalent metal cation.
- the electrolyte having a multivalent metal cation may be ferric sulphate or ferric chloride and acts as a coagulant by forming the hydroxide of the metal cation which absorbs suspended solids in the water being treated.
- the electrolyte may comprise aluminium sulphate which provides further cations to aid coagulation.
- the weighting agent is preferably calcium sulphate in the form of a moderately finely divided powder.
- the composition preferably also comprises a clay, for example a montmorillonite such as bentonite (available under the name FULBENT), or a kaolinite.
- a clay for example a montmorillonite such as bentonite (available under the name FULBENT), or a kaolinite.
- Such materials have the ability to absorb large quantities of water into their structure. Consequently, by adjusting the quantity of, for example, bentonite, the composition may be in the form of a pumpable slurry or in the form of a friable solid. In the latter case, the composition may take the form of briquettes.
- the mixture may also be solidified by the addition of an organic titanate such as that employed to solidify paints.
- the effect of the calcium sulphate is to absorb some organic matter from the water to be treated and to provide weight to suspended solids formed by the action of the electrolyte, so as to speed up separation and sedimentation.
- composition used in the method of the present invention tends to lower the pH of the water to which it is added.
- the pH should not fall below 5.5.
- the composition may also include an anionic or cationic polyelectrolyte in order to assist flocculation of suspended particles.
- the acidity of the composition is then an advantage, particularly when an anionic polyelectrolyte is used, because this has a stabilising effect on the polyelectrolyte.
- the cationic polymer stabilises the composition is unexpected; it would normally be expected to destabilise such a composition. It is theorized that, in a concentrated solution, the polymer recoils and remains so until diluted into use.
- a preferred composition in accordance with the present invention comprises an aqueous slurry containing ferric sulphate, calcium sulphate dihydrate, bentonite and a cationic polyelectrolyte.
- the composition may also contain aluminium sulphate.
- the composition comprises ferric chloride or ferric sulphate as the electrolyte
- the composition is preferably added to the water to be treated at the rate of 30-50 parts per million of ferric chloride or ferric sulphate.
- the overall dosage is preferably up to 100 parts per million of dry solids of the composition. In some instances higher dosages may be required.
- the likely dosage rate required in the process of British Patent Application No. 8208603 under comparable conditions is in most cases about 200 parts per million. In soft waters very low dosages of the new composition will suffice.
- the method of the present invention may be utilized with a split-dosing technique.
- a very small (for example 1 ppm) first dose is added to the water to be treated, followed by a second larger dose.
- Such a split-dosing technique reduces the total amount of composition used when compared with a single dosing technique; the resulting sludge is denser and the supernatant liquor is clearer.
- the first dose is believed to act as a pre-nucleating agent providing many nuclei about which the floc forms on addition of the second dose.
- compositions in accordance with the present invention were prepared as follows:
- Composition B was prepared in much the same way as Composition A, except that half of the ferric sulphate was replaced by aluminium sulphate. The resulting slurry was more mobile than composition A and again proved stable and reactive after several days.
- Composition B contained:
- composition A gave rapid floc formation (floc formed in 2 minutes) and even after only 10 minutes settling a clear supernatant liquor formed in which the suspended solids were less than half that in the sample treated with ferric sulphate alone.
- Composition B was used at a dose of 200 ppm and floc formation commenced within 1 minute of addition. The supernatant liquor formed more quickly than that in either (1) or (2) and the final liquor was the clearest of the three tests.
- compositions A and B were superior to straight ferric sulphate treatment and at far lower dosages of multivalent cationic coagulants.
- compositions A and B gave a denser sludge than the coagulating agents when used alone.
- compositions in accordance with the present invention facilitate treatment of potable waters, sewage and effluents by means of one combined composition which is easy to deliver, handle and supply and which may be tailored to suit individual requirements over a wide range of usage. This is of particular importance in small unmanned works and where sophisticated technical supervision is not available.
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Hydrology & Water Resources (AREA)
- Life Sciences & Earth Sciences (AREA)
- Inorganic Chemistry (AREA)
- Separation Of Suspended Particles By Flocculating Agents (AREA)
- Physical Water Treatments (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
- Water Treatment By Sorption (AREA)
- Removal Of Specific Substances (AREA)
Abstract
Description
Claims (14)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB848409410A GB8409410D0 (en) | 1984-04-11 | 1984-04-11 | Water treatment |
GB8409410 | 1984-04-11 |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US06721914 Continuation | 1985-04-11 |
Publications (1)
Publication Number | Publication Date |
---|---|
US4783265A true US4783265A (en) | 1988-11-08 |
Family
ID=10559534
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US06/925,500 Expired - Fee Related US4783265A (en) | 1984-04-11 | 1986-10-29 | Water treatment |
Country Status (6)
Country | Link |
---|---|
US (1) | US4783265A (en) |
EP (1) | EP0159178B1 (en) |
AT (1) | ATE55970T1 (en) |
CA (1) | CA1249081A (en) |
DE (1) | DE3579350D1 (en) |
GB (2) | GB8409410D0 (en) |
Cited By (20)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4906386A (en) * | 1988-11-03 | 1990-03-06 | Betz Laboraties, Inc. | Flocculation of coal fines with polyelectrolytes and electrolyte |
US5133870A (en) * | 1988-06-20 | 1992-07-28 | Heidenreich Hans J H | Treatment of aqueous dispersions |
DE4223285A1 (en) * | 1992-07-15 | 1994-01-20 | Sued Chemie Ag | Denitrification of waste water with a nitrate content - by mixing with activated sludge and organic sludge |
US5453206A (en) * | 1991-05-27 | 1995-09-26 | Modern Environmental Service Trust | Process for removing silica from aqueous liquors |
AT400708B (en) * | 1991-02-08 | 1996-03-25 | Sued Chemie Ag | Process for cleaning up slaughterhouse wastewaters |
US5506096A (en) * | 1989-02-28 | 1996-04-09 | Biobalance A/S | Method for controlling and/or monitoring biological processes |
US5510037A (en) * | 1993-02-12 | 1996-04-23 | Tastayre; Gilles | Regeneration of used cleaning solution |
US5611934A (en) * | 1995-12-18 | 1997-03-18 | Hoechst Celanese Corporation | Process for dye removal |
WO2001098215A1 (en) * | 2000-06-22 | 2001-12-27 | Nina Nikolaevna Stremilova | Composition for cleaning up natural water and sewage water and method for producing said composition (variants) |
US6444128B1 (en) | 1998-07-27 | 2002-09-03 | Power Engineering Company | Organic waste removal from process streams |
KR100799261B1 (en) | 2007-02-01 | 2008-01-29 | (주) 빛과환경 | Method for dewatering sludge to enhance its recycling usability with titanium salts as dewatering coagulant aid |
US20080203015A1 (en) * | 2007-01-09 | 2008-08-28 | Marston Peter G | System and method for enhancing an activated sludge process |
US20100155327A1 (en) * | 2007-01-09 | 2010-06-24 | Steven Woodard | System and method for enhancing a wastewater treatment process |
US20120261342A1 (en) * | 2008-12-05 | 2012-10-18 | Gilles Tastayre | Process for improving the precipitation of calcium and/or magnesium salts in the regeneration of used alkaline cleaning solution |
US8540877B2 (en) | 2007-01-09 | 2013-09-24 | Siemens Water Technologies Llc | Ballasted sequencing batch reactor system and method for treating wastewater |
US8623205B2 (en) | 2007-01-09 | 2014-01-07 | Siemens Water Technologies Llc | Ballasted anaerobic system |
US8840786B2 (en) | 2007-01-09 | 2014-09-23 | Evoqua Water Technologies Llc | System and method for removing dissolved contaminants, particulate contaminants, and oil contaminants from industrial waste water |
US9651523B2 (en) | 2012-09-26 | 2017-05-16 | Evoqua Water Technologies Llc | System for measuring the concentration of magnetic ballast in a slurry |
US10919792B2 (en) | 2012-06-11 | 2021-02-16 | Evoqua Water Technologies Llc | Treatment using fixed film processes and ballasted settling |
US11130686B2 (en) | 2017-01-10 | 2021-09-28 | Vermeer Manufacturing Company | Systems and methods for dosing slurries to remove suspended solids |
Families Citing this family (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1988007026A1 (en) * | 1986-01-16 | 1988-09-22 | Kelet-Magyarorsza^´Gi Vizügyi Tervezo^" Va^´Llalat | Process for treating microdispersed emulsions and liquids containing organic impurities |
DE4138666A1 (en) * | 1991-11-25 | 1993-05-27 | Sued Chemie Ag | METHOD FOR PRE-CLEANING SEWAGE |
DE69421283D1 (en) * | 1994-11-28 | 1999-11-25 | Aska Planning Co Ltd | Flocculants for wastewater treatment |
FR2766733B1 (en) * | 1997-08-01 | 1999-10-08 | Lms World Water Treatment | PROCESS AND PRODUCT FOR THE TREATMENT AND PURIFICATION OF EFFLUENTS AND COMPLEX FLUIDS |
AU1607000A (en) * | 1998-11-07 | 2000-05-29 | Procter & Gamble Company, The | Process and composition for water recycle |
GB2351730A (en) * | 1999-07-05 | 2001-01-10 | Procter & Gamble | Treatment of laundry water |
EP2168920A1 (en) * | 2008-09-25 | 2010-03-31 | Unilever N.V. | Water purification composition and method |
US20100140181A1 (en) | 2008-12-05 | 2010-06-10 | Gilles Tastayre | Regeneration of used cleaning solution |
Citations (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB516706A (en) * | 1938-07-05 | 1940-01-09 | John Oswald Samuel | Improvements in and relating to the flocculation of sewage suspensions and sludges |
US3493499A (en) * | 1968-05-16 | 1970-02-03 | Dow Chemical Co | Flocculation of saline solid suspensions |
US3575854A (en) * | 1969-04-14 | 1971-04-20 | M & T Chemicals Inc | Rapid setiling of gelatinous precipitates |
US3578586A (en) * | 1966-03-24 | 1971-05-11 | Simonacco Ltd | Treatiment of slurries |
US3680698A (en) * | 1970-02-25 | 1972-08-01 | Occidental Petroleum Corp | Process for the treatment of slimes and waste solids |
US3697420A (en) * | 1968-03-19 | 1972-10-10 | Donald Stapf Blaisdell | Method and apparatus for treatment of aqueous liquor |
US3737037A (en) * | 1971-05-03 | 1973-06-05 | Atlantic Richfield Co | Drilling fluid treatment |
US3738933A (en) * | 1969-12-15 | 1973-06-12 | Tatabanyai Szenbanyak | Process for the reduction of the biochemical oxygen demand of sewage and for the recovery of the inherent protein |
US3953330A (en) * | 1972-08-25 | 1976-04-27 | Betz Laboratories, Inc. | Water-soluble cationic polymeric materials and their use |
JPS5399656A (en) * | 1977-02-09 | 1978-08-31 | Agency Of Ind Science & Technol | Method of purifying suspended waste water |
US4279756A (en) * | 1976-05-03 | 1981-07-21 | Commonwealth Scientific And Industrial Research Organization | Water clarification |
GB2095226A (en) * | 1981-03-24 | 1982-09-29 | Blue Circle Ind Plc | Process and composition for conditioning an aqueous system |
JPS58159814A (en) * | 1982-03-18 | 1983-09-22 | Mitsubishi Acetate Co Ltd | Adsorptive treatment |
US4415467A (en) * | 1981-03-05 | 1983-11-15 | Colloid Piepho | Agent for the purification of waste waters and process for its production |
US4425238A (en) * | 1981-03-25 | 1984-01-10 | Basf Aktiengesellschaft | Removal of anionic compounds from water |
US4450092A (en) * | 1982-06-11 | 1984-05-22 | Nalco Chemical Company | Reducing turbidity in turbid waters |
Family Cites Families (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3128249A (en) * | 1955-07-18 | 1964-04-07 | Dow Chemical Co | Method for clarifying water |
GB1081096A (en) * | 1964-08-18 | 1967-08-31 | Nikex Nehezipari Kulkere | Water treatment |
JPS5075562A (en) * | 1973-11-08 | 1975-06-20 | ||
FR2397863A1 (en) * | 1977-07-21 | 1979-02-16 | Technime Sa | EMULSIONS BREAKING PROCESS AND MEANS FOR IMPLEMENTING THIS PROCESS |
GB1596204A (en) * | 1978-02-14 | 1981-08-19 | Filters International Inc | Treatment of sewage |
SE7902651L (en) * | 1979-03-23 | 1980-09-24 | Boliden Ab | FLEXING AGENT, PROCEDURE FOR ITS PREPARATION AND ITS USE |
SE8100161L (en) * | 1981-01-13 | 1982-07-14 | Boliden Ab | PUMPABLE WATER PURIFICATION COMPOSITION CONTAINING IRON (II) SULPHATE AND PROCEDURE FOR ITS PREPARATION |
SE440497B (en) * | 1981-03-23 | 1985-08-05 | Boliden Ab | ALUMINUM CHLORIDE COMPOSITION FOR WATER PURIFICATION, SLAM DRAINAGE AND WATER DRAINAGE AND PROCEDURE FOR ITS PREPARATION |
SE437016B (en) * | 1981-03-23 | 1985-02-04 | Boliden Ab | ALUMINUM SULPHATE COMPOSITION FOR WATER PURIFICATION, PAPER SLIMMING AND WATER DRAINAGE, AND PROCEDURE FOR ITS PREPARATION |
FR2516397B1 (en) * | 1981-11-16 | 1988-01-15 | Rhone Poulenc Spec Chim | FLOCCULATION ADDITIVE AND PROCESS FOR THE PURIFICATION OF WATER |
IE55674B1 (en) * | 1982-09-24 | 1990-12-19 | Blue Circle Ind Plc | Compositions comprising mineral particles in suspension and method of treating aqueous systems therewith |
SE440897B (en) * | 1983-03-15 | 1985-08-26 | Boliden Ab | DISPERSION OF WATER PURIFICATION ENDAMAL CONTAINING IRON (II) + SULPHATE HEATHYDRATE |
-
1984
- 1984-04-11 GB GB848409410A patent/GB8409410D0/en active Pending
-
1985
- 1985-03-27 GB GB08507960A patent/GB2157278B/en not_active Expired
- 1985-04-10 AT AT85302509T patent/ATE55970T1/en not_active IP Right Cessation
- 1985-04-10 CA CA000478739A patent/CA1249081A/en not_active Expired
- 1985-04-10 EP EP85302509A patent/EP0159178B1/en not_active Expired - Lifetime
- 1985-04-10 DE DE8585302509T patent/DE3579350D1/en not_active Expired - Fee Related
-
1986
- 1986-10-29 US US06/925,500 patent/US4783265A/en not_active Expired - Fee Related
Patent Citations (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB516706A (en) * | 1938-07-05 | 1940-01-09 | John Oswald Samuel | Improvements in and relating to the flocculation of sewage suspensions and sludges |
US3578586A (en) * | 1966-03-24 | 1971-05-11 | Simonacco Ltd | Treatiment of slurries |
US3697420A (en) * | 1968-03-19 | 1972-10-10 | Donald Stapf Blaisdell | Method and apparatus for treatment of aqueous liquor |
US3493499A (en) * | 1968-05-16 | 1970-02-03 | Dow Chemical Co | Flocculation of saline solid suspensions |
US3575854A (en) * | 1969-04-14 | 1971-04-20 | M & T Chemicals Inc | Rapid setiling of gelatinous precipitates |
US3738933A (en) * | 1969-12-15 | 1973-06-12 | Tatabanyai Szenbanyak | Process for the reduction of the biochemical oxygen demand of sewage and for the recovery of the inherent protein |
US3680698A (en) * | 1970-02-25 | 1972-08-01 | Occidental Petroleum Corp | Process for the treatment of slimes and waste solids |
US3737037A (en) * | 1971-05-03 | 1973-06-05 | Atlantic Richfield Co | Drilling fluid treatment |
US3953330A (en) * | 1972-08-25 | 1976-04-27 | Betz Laboratories, Inc. | Water-soluble cationic polymeric materials and their use |
US4279756A (en) * | 1976-05-03 | 1981-07-21 | Commonwealth Scientific And Industrial Research Organization | Water clarification |
JPS5399656A (en) * | 1977-02-09 | 1978-08-31 | Agency Of Ind Science & Technol | Method of purifying suspended waste water |
US4415467A (en) * | 1981-03-05 | 1983-11-15 | Colloid Piepho | Agent for the purification of waste waters and process for its production |
GB2095226A (en) * | 1981-03-24 | 1982-09-29 | Blue Circle Ind Plc | Process and composition for conditioning an aqueous system |
US4425238A (en) * | 1981-03-25 | 1984-01-10 | Basf Aktiengesellschaft | Removal of anionic compounds from water |
JPS58159814A (en) * | 1982-03-18 | 1983-09-22 | Mitsubishi Acetate Co Ltd | Adsorptive treatment |
US4450092A (en) * | 1982-06-11 | 1984-05-22 | Nalco Chemical Company | Reducing turbidity in turbid waters |
Cited By (31)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5133870A (en) * | 1988-06-20 | 1992-07-28 | Heidenreich Hans J H | Treatment of aqueous dispersions |
US4906386A (en) * | 1988-11-03 | 1990-03-06 | Betz Laboraties, Inc. | Flocculation of coal fines with polyelectrolytes and electrolyte |
US5700370A (en) * | 1989-02-28 | 1997-12-23 | Biobalance A/S | Biological treatment plant controlled by fluorescence sensors |
US5506096A (en) * | 1989-02-28 | 1996-04-09 | Biobalance A/S | Method for controlling and/or monitoring biological processes |
AT400708B (en) * | 1991-02-08 | 1996-03-25 | Sued Chemie Ag | Process for cleaning up slaughterhouse wastewaters |
US5453206A (en) * | 1991-05-27 | 1995-09-26 | Modern Environmental Service Trust | Process for removing silica from aqueous liquors |
DE4223285A1 (en) * | 1992-07-15 | 1994-01-20 | Sued Chemie Ag | Denitrification of waste water with a nitrate content - by mixing with activated sludge and organic sludge |
US5510037A (en) * | 1993-02-12 | 1996-04-23 | Tastayre; Gilles | Regeneration of used cleaning solution |
US5611934A (en) * | 1995-12-18 | 1997-03-18 | Hoechst Celanese Corporation | Process for dye removal |
US5750035A (en) * | 1995-12-18 | 1998-05-12 | Hoechst Celanese Corporation | Process for dye removal |
US6444128B1 (en) | 1998-07-27 | 2002-09-03 | Power Engineering Company | Organic waste removal from process streams |
WO2001098215A1 (en) * | 2000-06-22 | 2001-12-27 | Nina Nikolaevna Stremilova | Composition for cleaning up natural water and sewage water and method for producing said composition (variants) |
GB2381266A (en) * | 2000-06-22 | 2003-04-30 | Nina Nikolaevna Stremilova | Composition for cleaning up natural water and sewage water and method for producing said composition (variants) |
US7465691B1 (en) | 2000-06-22 | 2008-12-16 | Nina Nikolaevna Stremilova | Composition for cleaning up natural water and sewage water and method for producing said composition (variants) |
US20080203015A1 (en) * | 2007-01-09 | 2008-08-28 | Marston Peter G | System and method for enhancing an activated sludge process |
US8673142B2 (en) | 2007-01-09 | 2014-03-18 | Siemens Water Technologies Llc | System for enhancing a wastewater treatment process |
US7695623B2 (en) * | 2007-01-09 | 2010-04-13 | Cambridge Water Technology, Inc. | System and method for enhancing an activated sludge process |
US20100155327A1 (en) * | 2007-01-09 | 2010-06-24 | Steven Woodard | System and method for enhancing a wastewater treatment process |
US10023486B2 (en) | 2007-01-09 | 2018-07-17 | Evoqua Water Technologies Llc | Ballasted sequencing batch reactor system and method for treating wastewater |
US8470172B2 (en) | 2007-01-09 | 2013-06-25 | Siemens Industry, Inc. | System for enhancing a wastewater treatment process |
US8506800B2 (en) | 2007-01-09 | 2013-08-13 | Siemens Industry, Inc. | System for enhancing a wastewater treatment process |
US8540877B2 (en) | 2007-01-09 | 2013-09-24 | Siemens Water Technologies Llc | Ballasted sequencing batch reactor system and method for treating wastewater |
US8623205B2 (en) | 2007-01-09 | 2014-01-07 | Siemens Water Technologies Llc | Ballasted anaerobic system |
US8845901B2 (en) | 2007-01-09 | 2014-09-30 | Evoqua Water Technologies Llc | Ballasted anaerobic method for treating wastewater |
US8702987B2 (en) | 2007-01-09 | 2014-04-22 | Evoqua Water Technologies Llc | Methods for enhancing a wastewater treatment process |
US8840786B2 (en) | 2007-01-09 | 2014-09-23 | Evoqua Water Technologies Llc | System and method for removing dissolved contaminants, particulate contaminants, and oil contaminants from industrial waste water |
KR100799261B1 (en) | 2007-02-01 | 2008-01-29 | (주) 빛과환경 | Method for dewatering sludge to enhance its recycling usability with titanium salts as dewatering coagulant aid |
US20120261342A1 (en) * | 2008-12-05 | 2012-10-18 | Gilles Tastayre | Process for improving the precipitation of calcium and/or magnesium salts in the regeneration of used alkaline cleaning solution |
US10919792B2 (en) | 2012-06-11 | 2021-02-16 | Evoqua Water Technologies Llc | Treatment using fixed film processes and ballasted settling |
US9651523B2 (en) | 2012-09-26 | 2017-05-16 | Evoqua Water Technologies Llc | System for measuring the concentration of magnetic ballast in a slurry |
US11130686B2 (en) | 2017-01-10 | 2021-09-28 | Vermeer Manufacturing Company | Systems and methods for dosing slurries to remove suspended solids |
Also Published As
Publication number | Publication date |
---|---|
EP0159178A2 (en) | 1985-10-23 |
CA1249081A (en) | 1989-01-17 |
ATE55970T1 (en) | 1990-09-15 |
DE3579350D1 (en) | 1990-10-04 |
EP0159178B1 (en) | 1990-08-29 |
GB8409410D0 (en) | 1984-05-23 |
GB2157278A (en) | 1985-10-23 |
EP0159178A3 (en) | 1987-05-13 |
GB2157278B (en) | 1987-10-21 |
GB8507960D0 (en) | 1985-05-01 |
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